Composite structures are commonly used as high-strength, low-weight materials. A composite structure includes one or more composite layers, wherein each composite layer includes a reinforcement material and a matrix material. The reinforcement material may include fibers. The matrix material may be a polymeric material, such as a thermosetting resin or a thermoplastic resin.
Fiber-reinforced composite structures may be manufactured by laying up multiple layers of fiber tow to form a reinforcement layup. The fiber tow generally includes a bundle of fibers (reinforcement material) impregnated with a matrix material. In fiber placement technologies, the fiber tow is generally supplied in strip/tape form from a bulk reel and is pressed onto the underlying layup at a compaction nip using a compaction roller. The fully assembled reinforcement layup is then cured and/or consolidated, as necessary, to from the composite structure.
When the matrix material of the fiber tow is a thermoplastic resin, the layup process typically requires heating to soften the thermoplastic resin and obtain layer-to-layer consolidation within the reinforcement layup. For example, a laser beam (e.g., an infrared laser beam) may be projected at or near the compaction nip to heat the fiber tow and/or the underlying layup during fiber placement. However, over time, the laser light may degrade the compaction roller.
Accordingly, those skilled in the art continue with research and development efforts in the field of laser-assisted fiber placement.